What tool is this in E55 trunk?
 

What is the tool on the far left with the looped end?

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I think it is a towing eye. I assume the end in the pouch is threaded.

This is an emergency towing loop. It is designed to be installed in a fitting located in the bumper. On your car, look for a small square door on the rear bumper face, and another door in the front bumper, usually in the lower grille on the passenger side (often adjacent to the foglamp). These doors are designed to be (gently) pried open. I'm certain your owner's manual discusses the loop installation process in some detail.